When I started this blog last year, my first posts were about organic food because I was doing a lot of reading about it at the time.  Tomorrow night I’m giving a presentation to the women’s group at my church titled “The dose makes the poison - will organic food make you healthy or waste your money?”  It’s mostly a summary of what I wrote last year, but I thought I’d post my notes anyway, as a recap.  You can read the original posts here, here, here, and here.

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    In our modern American lives we have a huge amount of variety in our diets (if we choose to) and a huge variety of foods to choose from at the grocery store.  One of those choices is between organic and conventionally grown foods, especially now that organic food is so widely available that you can buy it at almost any grocery store - even at Wal Mart.

    100 years ago, all food was organic.  There were no synthetic pesticides or fertilizers, no artificial growth hormones, and no genetic engineering.  All that changed around the time of WWI.  The first big change was the invention of the Haber-Bosch process, which is turning methane and nitrogen gas into nitrate for fertilizer.  Before this reaction was discovered, the only way to fertilize crops was through crop rotation and natural fertilizers.

    Farmers soon learned that combining synthetic fertilizer with pesticides and modern farm machinery gave much higher yields than they could achieve before.  You’ve probably heard of the Green Revolution, and what that’s referring to is the work of the plant breeder Norman Borlaug.  In 1945 he took the results of a 20-year wheat breeding program, along with synthetic fertilizer and other modern farm implements, to Mexico.  His program turned the country from a wheat importer to a wheat exporter.  Then he repeated the success in India in the 1960s and China in the 1980s, and his work is widely credited with allowing food production to keep pace with worldwide population growth.  He was awarded the Nobel Peace Prize in 1970.

    So modern agriculture, or conventional agriculture, has been good at feeding the world.  But its tools do have their problems, and a backlash against it sort of started simmering in the 1960s and 70s, and then over the last 20 years the organic food market really took off and has consistently grown by about 20% per year.  There are a lot of voices who say organic food is healthier for humans and the environment than conventional food.  That may be true.  On thing that’s certain is that it’s more expensive.  I want to be healthy, just like most people do, but I also care about my grocery bill.  So I think it’s important to know about what the differences between organic and conventional food are, and whether or not there will be health benefits that are worth paying for.

    But first, what does it mean to be certified organic?

    No synthetic fertilizers

    No synthetic pesticides or herbicides

    Not irradiated

    Not genetically engineered

    Livestock raised without antibiotics or artificial growth hormones

    Food additives must be on the National Organic Program’s list of approved substances

    Organic farmers use crop rotation, manure, and compost in place of synthetic fertilizers, and mulching, natural pesticides, and hand weeding instead of pesticides and herbicides.  In order to understand which implements in conventional agriculture could be dangerous, I think it’s helpful to break things out into categories of foods: fruits & vegetables, grains, meat & poultry, and dairy.

Fruits & vegetables

Pesticides

    The main concern here is pesticides & herbicides.  Why are these a worrisome?  Because they are toxic – that’s the reason they can kill bugs and weeds.  Various pesticides have been shown cause a wide range of problems in lab animals, like birth defects, nerve damage, cancer, immune dysfunction, and fertility problems.  And infants & children are particularly sensitive because they eat more in proportion to their body weight than adults do.  But eating foods grown with pesticides isn’t the same as drinking a teaspoon of poison.  Levels do matter.

    So the important question is: Are the amounts of pesticides found on fruits & vegetables safe?

    Here’s a little story to help answer it: In 1993, the National Academy of Sciences (the premier professional association for scientists in the US) released a report called “Pesticides in the Diets of Infants and Children” that basically said safety levels for pesticides weren’t being determined by health considerations, they were being determined by best practices in agriculture.  Seriously.  Not based on health considerations.  In response to that, Congress passed the Food Quality Protection Act of 1996, which required the EPA to develop health-based standards for 9,600 pesticides within 10 years.  That was completed in 2006.  Some pesticides were taken off the market, others remained because they could meet the standards of the FQPA.

    I think this story is at the same time comforting and scary.  Scary because it took over 50 years from the time pesticide use became ubiquitous for the government to take a close look at the safety of pesticides levels in our food.  Over 50 years for the EPA to do a systematic study of the heath effects of pesticides!  But it’s comforting to know that’s now been done, and the EPA can now say with some authority that the levels of pesticides in our food are safe.

    On the other hand, the Organic Center, which is a reputable non-profit organization, believes that the only acceptable level of pesticides in food is zero.  But really, levels do matter.  As Paracelcus, known as the father of toxicology said – the dose makes the poison. 

    A quick example of what I mean.  In 2002 a group of Swedish researchers discovered that a chemical called acrylamide is produced in potatoes cooked at high temperatures.  Acrylamide is a neurotoxin and possibly a carcinogen, so people got worried about eating french fries and chips.  But it turns out the average woman would have to eat 92 pounds of fries a day in order to consume half the dose of acyrlamide that the World Health Organization says would give an adverse affect.  In spite of this, the California attorney general’s office sued four major food manufacturers for not listing acrylamide as a potential carcinogen in their products.  They settled out of court for $2 million.

    This is ridiculous.  It’s an example of chemists’s ability to detect vanishingly small quantities of chemicals, matched with people’s natural tendency to worry, resulting fear trumping reason.

    Anyway, as for pesticides in our fruits & vegetables, there are so many different kinds of pesticides that there’s no way any of us have time to evaluate them all.  Ultimately, since no one has time to become a pesticide expert, we must all rely to some degree on authority.  Your authority could the EPA telling you pesticide levels are safe, or a group like the Organic Center saying the only truly safe level is zero. 

    My feeling is that I am not worried about the levels of pesticides in conventional foods.  But if kids or babies are eating a lot of a particular kind of food, it may make sense to buy that organic. Personally, I bought organic baby food.  But I don’t buy organic fruits & vegetables for my family in general.  If you have to peel something to eat it, like citrus or bananas, it’s absolutely not worth buying organic.  Washing and scrubbing fruits & vegetables and removing the outer leaves of leafy vegetables will help reduce pesticide exposure.  And if you want to be really careful, I’d look at the Dirty Dozen – it’s a list of the fruits & vegetables with the highest pesticides.  If you eat a lot of anything on this list, you might want to consider buying it organic.

Other issues with fruits & vegetables

Fertilizers – In my reading, I haven’t found any health concerns about synthetic fertilizer.  There are some serious environmental concerns, but I’m going to just stick to talking about food and nutrition here.

Irradiation – This means that foods are exposed to some kind of radiation that kills off bacteria that may be on them.  It doesn’t affect the safety of food at all, except maybe to improve it.  It sounds scary, but eating irradiated food is nothing like getting irradiated yourself.  The radiation doesn’t linger in the food.  It doesn’t make the food radioactive.

Genetic modification – This is a big issue.  There is a lot of scary literature out there claiming that GM crops are unhealthy for human consumption and bad for the environment.  But I wholeheartedly believe they are not.  You may know this, but all the corn and soybeans you’ve eaten in the past 10 years (unless they were organic) have been genetically modified.  It’s no big deal, because humans have been genetically modifying crops since the dawn of agriculture through breeding, we’re just doing it in a more high-tech way now.

Grains

    I’ve put grains in a separate category from fruits and vegetables because we usually buy them separately at the grocery store.  But the same categories of potentially dangerous agricultural inputs apply.  As it turns out, a 2008 report from The Organic Center said that grains are one of the foods with the very lowest pesticide levels.  Other foods listed as being very low in pesticides are onions, bananas, citrus, pineapple, meats, and poultry.  So I’d take that to mean that pesticides are of very little concern in grains.  These other categories – fertilizers, irradiation, and genetic modification, I don’t worry about either.

Meat and Poultry

    An organic apple costs a little more than a conventional one, but an organic steak costs a lot more.  So this is one area where I’d really want to know if there are significant differences between organic & conventional products, simply because I feel like I’d need a pretty good reason to buy organic meat (based on cost).

Pesticides

    There are three potentially bad things that show up in meat and poultry: pesticides, antibiotics, and artificial growth hormones.  The Organic Center report I just mentioned listed meat and poultry as being among the foods lowest in pesticides.  This makes sense because a lot of these animals are grain fed, and grains are very low in pesticides. 

Antibiotics

    Most livestock and poultry are fed antibiotics from cradle to grave, whether they’re sick or not.  This is to keep the animals from getting sick.  But it turns out that getting the actual antibiotics in your meat and milk isn’t very likely.  A 2008 I study I found in the Journal of the American Dietetic Association found no antibiotics in retail milk of any kind, and it’s equally unlikely that they’d be found in meat.  Routine use of antibiotics in agriculture is still a big problem though, because of drug resistance.  Drug resistant bacteria are a serious public health problem, and until recently it seemed like the problem came from overprescribing antibiotics.  But now it’s becoming clear that some of the antibiotic resistant infections people are getting can be traced back to antibiotic use in agriculture.  So that’s a problem, but not one that is likely to directly affect your health.

Hormones 

    Beef cattle are given a mix of anabolic steroids to make them grow faster.  Poultry and pigs don’t respond to these hormones as much and they’re not used in these animals.  The steroid hormones that cattle are given are related to human sex hormones.  And they do show up in meat.  A 2007 study showed that for women who ate a lot of beef while pregnant (that’s 7 or more meals a week), their sons had on average 25% lower sperm counts and they were three times more likely to have fertility problems.  Yikes.  Other areas of concern are that hormones in meat could affect the age of puberty for girls and affect breast cancer risk, but existing evidence is not conclusive on these issues.  One important consideration is that the amount of hormones people get from meat are very small compared with the amount of hormone produced in adult bodies regularly.  It’s also impossible to differentiate between naturally produced hormones in an animal and hormones that are there from hormone treatments.  Some studies show hormone levels to be slightly higher in treated animal’s milk and meat, but still within normal levels.

    So it’s hard to say exactly how risky eating hormone-treated beef is. The only way to be sure beef isn’t hormone treated is to buy organic.  Organic beef is pretty expensive, but if you’ll forgive me for giving a little more personal opinion here, meat is really more of a treat than a staple in most of the world, and in general Americans could do with eating a lot less of it.  That would be in keeping with the Word of Wisdom’s advice that the beasts and fowls of the air are to be used sparingly. 

Dairy

    The same bad things that could show up in meat and poultry could also show up in dairy: pesticides, antibiotics, and growth hormones.

Pesticides and antibiotics

    First, pesticides.  The Organic Center reviewed two years of USDA pesticide testing in milk (1998 and 2004) and they found that all milk samples they tested, whether organic or conventional, had some detectable pesticides.  But they were almost all DDT derivatives.  DDT is a long-banned pesticide that breaks down very slowly, and it’s everywhere – both on organic and non-organic farms.  They found virtually no contemporary-use pesticides in any kind of milk. 

    I already mentioned that antibiotics are pretty much undetectable in milk.

Hormones

    Dairy cows are often given recombinant bovine growth hormone (rBGH) to increase milk production.  It works by increasing the levels of another hormone called IGF-1, which is the same in cows and humans, and it definitely comes through in the milk.  Elevated IGF-1 is linked to cancer in humans, so that is a scary thought.  Organic milk cows aren’t given rBGH, but I’ve noticed that the store brands of milk in my local grocery stores all say their farmers pledge not to use rBGH.  So from a health point of view, there is probably not much difference between organic and conventional milk.  There is definitely a difference in the life of the cow, because organic cattle are required to have pasture time, while conventional cattle are not, but that is more of an animal rights issue than a health issue.

Conclusion

    I don’t think you can make a blanket statement that organic food is healthier than conventional food.  But there are certain agricultural inputs in certain kinds of food that you might be concerned about.  For me, those boil down to hormones in meat and pesticides in fruits and vegetables.  But even with those, I don’t think the evidence is so overwhelming that you really need to feel compelled to buy organic food.  You can avoid some of the riskier foods and by replacing them with safer kinds of conventional food, or buy organic in a selective way.